This will be an open-label study of C1 INH-IMMUNO in the treatment of attacks of hereditary angioedema (HAE). HAE is characterized by recurrent episodes of well circumscribed, nonpitting, subepithelial edema primarily involving the extremities, face, abdomen, and larynx. HAE is characterized by a marked decrease in functional C1 inhibitor. This study attempts to control the symptoms of HAE by administering C1 inhibitor.